1. Field of the Invention
The invention relates to devices for extinguishing fires.
2. Description of the Prior Art
The field of fire extinguishing devices is a highly developed one. Numerous organizations have promulgated guidelines and standards relating to the construction, testing, shipment and maintenance of fire extinguishing devices. The National Fire Protection Association and Underwriters Laboratories are especially prolific.
U.S. Pat. Nos. 117,891,297,075 and 430,866 disclose devices within a class of fire extinguishing devices generally known as fire extinguishing grenades. These devices are understood to be obsolete in the sense that they are not in general use today. Basically, a fire 15 extinguishing grenade comprises a closed, pressurized vessel containing a fire extinguishing media. The vessel is constructed of a frangible material so that the grenade, when thrown into or towards a fire, will break open upon impact, releasing the fire extinguishing media to do its work. U.S. Design Pat. No. 115,824 discloses an ornamental design for a fire extinguishing grenade.
U.S. Pat. No. 2,871,952 discloses an automatic fire extinguisher in the form of a Christmas tree ornament. The body of the ornament is adapted to hold a fire extinguishing liquid and compressed air. An impact element is held in place by a fusible link, against the action of a spring. When the fusible link is broken by exposure to heat, the impact element is released and it fractures a normally closed end portion of a hollow frangible stem which is in communication with the interior of the vessel, thereby releasing the liquid inside to extinguish the fire.
U.S. Pat. No. 3,132,695 discloses an automatic fire extinguisher in the form of a Christmas tree ornament. The body of the ornament can be made from metal and a thermally actuated valve assembly is provided on the bottom of the vessel. A fire extinguishing medium, such as carbon tetrachloride, and a propellant such as dichlorotetrafluoroethane are contained in the vessel. An opening in the vessel is normally plugged by a conical seal which is held in place by a flame sensitive screw. A highly flammable "trigger" is connected to the screw and it is adapted to quickly conduct flame to the screw, causing it to fail and release the conical seal so that the contents of the vessel will be discharged.
U.S. Pat. No. 3,171,493 discloses a fire extinguishing device for Christmas trees. The device comprises a heat actuated sprinkler head incorporated in an ornament, a canister containing a liquid fire extinguishing medium under pressure and a hose connecting the canister to the sprinkler head. The canister is provided with an auxiliary cartridge for making up pressure lost through the sprinkler head.